Canister lifter and holder for breathing apparatus



Nov. 2, 1954 w. c. HAMILTON 2,693,181

CANISTER LIFTER AND HOLDER FOR BREATHING APPARATUS Filed June 7, 1952 3 Sheets-Sheet 1 I I INVENTOR. Mum C. #flHll-TON 1954 w. c. HAMILTON 2,693,181

CANISTER LIFTER AND HOLDER FOR BREATHING APPARATUS Filed June 7, 1952 3 Sheets-Sheet 2 IN VEN TOR.

Nov. 2, 1954 w CQHAWLTQN 2,693,181

CANISTER LIFTER AND HOLDER FOR BREATHING APPARATUS 3. sheets sheet 3 Filed June 7, 1952 IN VEN TOR. 6d. Lin C. #1914 u. raw

A: fire/6415,05

United States Patent CAYTSTER LIFTER AND HOLDER FOR BREATHING APPARATUS William C. Hamilton, Pittsburgh, Pa., assignor to Mine Safety Appliances Company, Pittsburgh, Pa., a corporation or Pennsylvania Application June 7, 1952, Serial No. 292,323

13 Claims. (Cl. 128-191) This invention relates to oxygen breathing apparatus, and more particularly to apparatus for holding a removable canister and permitting it to be quickly replaced by a new one.

One type of oxygen breathing apparatus has a slide valve with an opening in its bottom for receiving the neck of a removable oxygen generating canister that is movable vertically in a sleeve-like guard below the valve. When the canister is spent, it is necessary to replace it with a new one. This must be done very quickly to prevent impure air from entering the breathing apparatus and to renew the generation of oxygen as soon as possible. When the breathing apparatus is being made ready for use it is desirable to retain a new canister in a stand-by position.

It is among the objects of this invention to provide such oxygen breathing apparatus in which canisters can be changed in only a few seconds, in which an unused canister can be held in a stand-by position until needed, in which a spent canister can be quickly forced out of the apparatus, in which provision is made to compensate for wear or variation in slide valve or canister parts, and in which the slide valve is held unseated when the apparatus is, not in use.

In accordance with this invention supporting means are provided adjacent the bottom of the slide valve for pivotally supporting a pair of laterally spaced arms on opposite sides of the valve near its front. These arms normally extend forward and backward from their pivots. A handle is connected to the front ends of the arms and is adapted to beswung upward to swing their rear ends down in order to permit the neck of an oxygen generating canister to be moved up between them. The rear ends of the arms are provided with means for engaging the bottom of the enlarged upper end of the canister neck to push it upward to actuate the valve when the handle is swung downward again. Resilient means connect the upper end of the handle with the front ends of the arms, and means are provided for detachably connecting the lower part of the handle to the guard that surrounds the canister. For engaging and lifting the canister, the rear ends of the arms preferably are provided with pawls which also are formed to engage the lower end of the sliding portion of the valve in the absence of a canister and to lift it only far enough to unseat the valve. Projecting from the handle into the guard is a member which engages the bottom of the enlarged upper end of the canister neck to support the canister in a stand-by position below the lifting arms when the apparatus is not in use.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which Fig. 1 is a front view, with parts broken away, of the slide valve and canister guard lifter with the canister in stand-by posi tion; Fig. 2. is a side view with part of the guard broken away; Fig. 3 is a front view with the handle raised and the top of the canister neck pushed up into the slide valve; Fig. 4 is a side view of the preceding figure with parts broken away; Fig. is a side view, partly in section, of the apparatus in operating position; and Fig. 6 is a horizontal section of the valve and plan view of the guard taken on the line VI-VI of Fig. 1.

Referring to the drawings, an upright sleeve-like guard 1 for an oxygen generating canister 2 is supported by a curved breast plate 3 that can be strapped against the chest of a person in any well-known manner. In actual practice the wall of the guard is provided with a large ing bag (not shown).

when the canister is pushed up against the point. "upper end of the canister neck is provided with an en- 2,693,181 Patented Nov. 2, 1954 number of holes to reduce its weight, and it may be covered with insulating material to help protect the wearer from the heat produced by the canister. Extending across the top or' the guard from its front back to the top of the breast plate are a pair of laterally spaced metal brackets 4 that have parallel vertical flanges 5 and inwardly bent fingers 6 above the flanges. tending througn openings in the ends of these ringers are screws 7 which support between the brackets a slide valve 8 like the one shown in the copending patent application of myself and Frank Bub, S. N. 277,408, filed March 19, 1952. As shown in Figs. 1 and 6, this valve has a cylindrical casing 10 provided in its top with an inlet port 11 adapted to be connected to the exhalation tube of a face-piece (not shown). The side of the casing is provided with an outlet 12 for connection to a breathis connected to one end of a tubular elbow '13 supported by a metal strip 14 from one of the brackets 4. The outlet of the elbow is adapted to be connected to the inhalation tube of the face-piece.

Inside the valve casing there is a valve seat 16 around the lower end of the inlet port. Directly below this seat there is a vertically movable sleeve valve 17 that has a flange 18 around its lower end which is pressed downward by a coil spring 19. The bottom of the flange normally seats against a lower valve seat 21, but the sleeve valve can be pushed upward into engagement with upper seat 16 by means of a skirt 22 (Fig. 5) slidably mounted in the lower part of the valve. This skirt has a flaring lower end encircled by a rubber ring 23 suspended from the casing. Extending up into the sleeve valve and projecting below the skirt is a tubular member 24 provided with a perforated point 25 for piercing the conventional seal in the neck of an oxygen generating cani itfir circling flange 27 on which a rubber-like sealing ring 28 is mounted. As is well known, the canister is filled with a chemical that will generate oxygen when it is exposed to the moisture in the exhaled breath of the person wearing this apparatus.

Extending through holes in the front ends of bracket flanges 5 are hinge pins, with threaded ends 30 that serve as pivots for a forked member 31 that extends forward and then curves downward for attachment to the upper end'of a channel shape member 32. These two members form a handle that can be swung up to horizontal position, as shown in Fig. 4. Rigidly mounted in the lower end of the handle is a bracket 33, as shown in Figs. 1 and 5, that has vertically spaced flanges provided with axially aligned holes. A latch 34 is slidably mounted in these holes and has a tapered upper end projecting from the upper flange. The latch is urged upwardly by an encircling coil spring 36 compressed between the lower flange and a pin 37 that extends through the latch directly below the upper flange. The ends of the pin also extend through an inverted U-shape slide 38, the opposite sides of which slide in notches in the sides of the bracket flanges. The point of the latch normally projects up behind the head of a pin 39 projecting from the front of the guard through slide 38. When it is desired to release the handle from this pin, the wearer inserts a finger through a hole 40 in the handle and presses down on the U-shape slide in order to cause pin 37 to depress the latch.

Above the handle locking mechanism just described there is a pin 42 extending across the handle with its ends mounted in the opposite sides of the channel member 32. Pivotally mounted on this pin are parallel ears at the lower end of a lever 43, the upper end of which is urged backward away from the handle by a wire spring 44 looped around the pin and having portions pressing against the inner surfaces of the lever and handle as shown in Fig. 4. The upper end of the lever projects through an opening 46 in the front of the guard and will support a canister in stand-by position in the guard by projecting under neck flange 27, as shown in Fig. 2. When a canister is first pushed up into the guard, sealing ring 28 on top of its neck first engages the lever and swings it outward against the The outlet of the breathing bag 3 resistance of spring 44'. As soon as. the .neck flange passes the lever the latter swings back toward the neck of the canister. Upward movement of the canister at this time is limited by a stop 47 projecting .through guard opening 46 from the handl'eabove'l'ever 43 Also pivotally mounted on pivot pinsf30' are a pair of arms 50 that are integrally connected. in front of the guard by a crossbar 51. This cross bar normally rests on top of the handle at the upper end of channel member 32, on which it is held 'by pins. 52. extending.

slidably through them. The pins project a' considerable distance down through the handle and support coil springs 53 that are'compressed between the handle and heads on the lower ends of the pins. normally hold cross barSl and the handle tightly together so that arms 50 are moved with the handle. When the handle is in its lower position, the arms extend'rearwardly from pivot pins 30 to points about halfway back along the opposite sides of the slide valve, as shown in Figs. 2, 5 and 6. .Projectingfrom the inner surfaces of the. rear ends of the arms are pawls 54 which preferably are cylindricaL- As shown in Figs. 1 and 3, the pawls have large inner ends connected to the arms by necks of smaller diameter. They are so formed and positioned that the bottom of valve skirt 22 rests on the necks, and the necks hold the skirt in a. slightly elevated position in which it lifts the sleeve valve 117 from lower seat 21 but does not allow the sleeve valve to engage upper seat 16. Consequently, as shown in Fig. 1, as long as the canister is absent or is in stand-by position in the guard the sleeve valve is held out of engagement with both valve seats and therefore there is no chance of the valve being impaired by the continuous pressure of the sleeve valve against either seat over a long period of time.

When it is desired to use the breathing apparatus the handle is swung forward and up to the position shown in Fig. 4, which swings pawls 54 down .to the front wall of the guard. The hand is heldunder the canister at this time to support it, because the handle swings lever 43 away from the canister: neck. With stop 47 and the pawls out of the way, the canister can be pushed upward by hand until the top of the canister engages the lowered pawls. In being moved up this far the seal in the neck of the canister is pierced by the point of tubular member 24 of the valve, and-sealing, ring 28 enters the lower end of the flaring valve skirt 22. The handle is then swung down again, causing the large inner ends of pawls 54 to engage the bottom of neck flange 27 of the canister and force the canister upward as shown in Fig. 5. This causes the sealing ring to engage the skirt and push the sleeve valve 17 ;up until it engages upper seat 16,- which normally occurs while the lower end of thehandle is. still aninch ormore away from the guard. Continued movement of the handle back toward the guard until it islocked on pin 39 will compress coil springs 53 and separate the handle from arm cross bar 51. Because of this resilient connection between the handle and arms 50, the sleeve valve 17 is always resiliently pressed against'th'e upper valve seat even though there is wear in the parts or variation. in canister dimensions.

Because of the heat generated. by the canister, there may be times when sealing ring. 28 will tend to stick to the valve skirt 22 when it is desired to remove a spent canister.

lifted pawls 54 will be swung down against the top of the canister and will push it down away from the valve to strip the sealing ring from the skirt- It takes only about three seconds to change a canister with this apparatus.

According to the provisions of the patent statutes, I have explained the principle of my invention .and have illustrated and described what. I now consider to represent its best embodiment. it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

1. In oxygen breathing apparatus, a guard, a vertically movable oxygen generating canister removably disposed 7 1n said guard andhaving a neck with an; enlarged upper end, a slide valve above the guard provided with .an.

opening in its bottom for reception of said' enlarged These springs.

However, this will not cause any delay in ejecting the canister, because when the handle is- However, .I desire to have upper end .ofthe canister neck and. also provided with.

a vertically movable valve member above said opening; and apparatus for moving: the canister upward and holding it in its upper position comprising supporting means adjacent the bottom of the valve, 21 pair of laterally spaced arms pivotally' connected to said means on opposite sides of the valve near its front and normally extending forward and backward therefrom, a handle connected with the front 'ends of the arms and adapted to be swung upward. to swing their rear ends down to permit the neck of the canister to be moved up behind them, and means on said rear ends of the arms for engaging the bottom of the enlarged upper end of the canister neck to push it upward to raise the valve member when said handle is swung downward again.

2. In oxygenbreathing apparatus, a guard, a vertically movable oxygen generating canister removably disposed in said guard and having a neck withan .enlarged upper end, a slidevalve above the guard provided with an opening in its bottom for reception of of the arms, the handle beingv adapted to be swung upward to swing'th'e' rear ends of the arms down to permit the neck of the canister to be moved 'up behind them, means'on said rear ends of thearmsfor engaging.

the "bottom of the enlarged upper end of the 'canister neck to push 'itupwardto raise the valve member when said handle is swung. downward towardthe guard, said resilient means being adapted to permit the handle to continue to be moved toward the guard after upward movement of the rear ends of said arms has been arrested; and means fondetachably connecting the lower part of thehandle to the guard.

3 In oxygen breathing apparatus, a guard, a. vertical- 1y movable oxygen generating canister removably dis.- posed' in said guard and having a neck with an enlarged upperend, a slide valve above the guard provided with an opening in. its bottom for reception of said enlarged upper end of the canister neck. and also provided with a vertically movable valve member above said opening;

and apparatus for moving the canister upward .andv holding it in its upper position comprisingv supporting means adjacent. the bottom. of the valve, a pair of .laterally spaced arms pivotally connected to said means on opposite sides ,of the valve near its frontand normally .extending forward and backward therefrom, a handle in front of the guard. having its. upper end' pivoted to said supporting means on the .same axis-as said arms, resilient meansconnecting the: front end'sof the. arms with the upper end of the .handle,..the fhandle being adapted to he swung upward to swing the rear endsof the arms down'to permit the .neck of the canister to be .moved up behind them, means onsaid rear ends of the armsufor engagingthe bottom .of' the enlarged upper end of the canister neck to push it .upward'to' raise. thev valve member when said handle is swung downward toward. the guard, said resilient means being adapted to :permit :the handle to continue to be moved toward the guard after upward movement of :said arms has been arrested, and means for detachabl'y connecting. the'l'ower part of the handle to the guard.

4. In oxygen breathing apparatus, aguard, a vertical 1y movable oxygen. generating. canister removably dis.- posed in said guard andhavi'nga neck with an enlarged. upper end, a slide valve above theguard provided with an opening in .its bottomfor reception 'of said enlarged upper end ofrthe canister neck andalso provided with a vertically movable valvemember above said opening; and apparatus. for moving, the canister upward and. holding it in its upper position comprising supportingmeans adjacent the bottomv of .the valve, a pair of laterally spaced arms pivotally connected to said means on .oppo'site sides of the valve .near .its front and normally extending forward. .and backward therefrom, ,a. handleconnectedwi'th .thefront ends-of the armsandadapted to be swung upward to swing their rear ends down to permit theneck of the canister to be moved up behind them, and pawlsmounted on said rear ends of the arms and having curved upper surfaces for engaging the bottom of the enlarged upper end of the canister neck to push it upward to raise the valve member when said handle is swung downward again.

5. in oxygen breathing apparatus, a guard, a verticalposed in said guard and having a neck with an enlarged upper end, a slide valve above the guard provided with an opening in its bottom for reception of said enlarged upper end of the canister neck and also provided with a vertically movable valve member above said opening; and apparatus for moving the canister upward and holding it in its upper position comprising supporting means adjacent the bottom of the valve, a pair of laterally spaced arms pivotally connected to said means on opposite sides of the valve near its front and normally extending forward and backward therefrom, a handle in front of the guard having its upper end pivoted to said supporting means on the same axis as said arms, a cross memberrigidly connecting the front ends of the arms and normally resting on the handle, a pair of pins secured to said cross member and extending toward the lower end of the handle through holes in its upper part, coil springs on said pins compressed against the lower surface of said upper end of the handle, the handle being adapted to be swung upward to swing the rear ends of the arms down topermit the neck of the canister to be moved up behind them, means on said rear ends of the arms for engaging the bottom of the enlarged upper end of the canister neck to push it upward to raise the valve member when said handle is swung downward toward the guard again, said resilient means being adapted to permit the handle to continue to be moved toward the guard after upward movement of said arms has been arrested, and means for detachably connecting the lower part of the handle to the guard.

6. In oxyygen breathing apparatus, a guard, a vertically movable oxygen generating canister removably disposed in said guard and having a neck with an enlarged upper end, a slide valve above the guard provided with an opening in its bottom for reception of said enlarged upper end of the canister neck and also provided with a vertically movable valve member above said opening; and apparatus for moving the canister upward and holding it in its upper position comprising supporting means adjacent the bottom of the valve, a pair of laterally spaced arms pivotally connected to said means on opposite sides of the valve near its front and normally extending forward and backward therefrom, a handle in front of the guard having a bifurcated upper end straddling both arms and pivoted to said supporting means on the same axis as the arms, the front ends of said arms overlying an upper part of the handle so that when the handle is swungupward it will swing the rear ends of the arms down to permit the neck ofi the canister to be moved up behind the arms, resilient means connecting the front ends of the arms to said upper part of the handle, means on said rear ends of the arms for engaging the bottom of the enlarged upper end of the canister neck to push it upward to raise the valve member when said handle is swung downward toward the guard, said resilient means being adapted to permit the handle to continue to be moved toward the guard after upward movement of said arms has been arrested, and means for detachably connecting the lower part of the handle to the guard.

7. in oxygen breathing apparatus, a guard, a vertically movable oxygen generating canister removably disposed in said guard and having a neck with an en larged upper end, a slide valve above the guard provided with an opening in its bottom for reception of said enlarged upper end of the canister neck and also provided with a vertically movable valve member above said opening; and apparatus for moving the canister upward and holding it in its upper position comprising a pair of laterally spaced brackets rigidly mounted on top of the guard and supporting the valve between them, a pair of laterally spaced arms pivotally connected to the front ends of said brackets and normally extendingfrom their pivot points backward between the brackets and forward therefrom, a handle connected with the front ends of the arms and adapted to be swung upward to swing their rear ends down to permit ly movable oxygen generating canister removably dissaid handle is swung downward again.

8. In oxygen breathing apparatus, a guard, a vertically movable oxygen generating canister removably disposed in said guard and having a neck with an enlarged upper end, a slide valve above the guard provided at its bottom with a vertically movable skirt for reception of said enlarged upper end of the canister neck and also provided with a vertically movable valve member above the skirt; and apparatus for moving the canister upward into the skirt and holding it in its upper position comprising supporting means adjacent the bottom of the skirt, a pair of laterally spaced arms pivotally connected to'said means on opposite sides of the valve near its front and normally extending forward and backward therefrom, a handle connected with the front ends of the arms and adapted to be swung upward to swing their rear ends down to permit the neck of the canister to be moved up behind them, and means projecting from the inner faces of said rear ends of the arms for engaging the bottom of the enlarged upper end of the canister neck to push it and said valve skirt upward to raise the valve member when said handle is swung downward again, said last-mentioned means being formed to engage the lower end of the valve skirt in the absence of a canister and to lift it.

9. In oxygen breathing apparatus, a guard, a vertically movable oxygen generating canister removably disposed in said guard and having a neck with an enlarged upper end, a slide valve above the guard provided with an opening in its bottom for reception of said enlarged upper end of the canister neck and also provided with a vertically movable valve member above said opening; and apparatus for moving the canister upward and holding it in its upper position comprising supporting means adjacent the bottom of the valve, a pair of laterally spaced arms pivotally connected to said means on opposite sides of the valve near its front and normally extending forward and backward therefrom, a handle connected with the front ends of the arms and adapted to be swung upward to swing their rear ends down to permit the neck of the canister to be moved up behind them, means on said rear ends of the arms for engaging the bottom of the enlarged upper end of the canister neck to push it upward to raise the valve member when said handle is swung downward again, and a member projecting from the lowered handle into the guard and adapted to engage the bottom of said enlarged portion of the canister neck to support the canister in a stand-by position below said arms.

10. In oxygen breathing apparatus, a guard, a vertically movable oxygen generating canister removably disposed in said guard and having a neck with an enlarged upper end, a slide valve above the guard provided with an opening in its bottom for reception of said enlarged upper end of the canister neck and also provided with a vertically movable valve member above said opening; and apparatus for moving the canister upward and holding it in its upper position comprismg supporting means adjacent the bottom of the valve, a pair of laterally spaced arms pivotally connected to said means on opposite sides of the valve near its front and normally extending forward and backward therefrom, a handle connected with the front ends of the arms and adapted to be swung upward to swing their rear ends down to permit the neck of the canister to be moved up behind them, means on said rear ends of the arms for engaging the bottom of the enlarged upper end of the canister neck to push it upward to raise the valve member when said handle is swung downward again, a stop member projecting from the upper part of the lowered handle into the guard below said arms to limit upward movement of a canister in the guard, and a movable member projecting from the handle into the guard below said stop member and adapted to engage the bottom of said enlarged portion of the canister neck to support the canister in standby position below the stop member, said movable member being movable outward toward the handle by means of the canister when the canister is first pushed up into the guard, whereby to permit said enlarged upper end to slide past the inner end of said movable member.

anagram II. In oxygen breathingapparatus, a canister guard, aqvertically movable oxygen generating canister removably disposed in said guard and having a neck with an enlarged upper end, a slide valve mounted on top of the guard and provided at its bottom with a sliding skirt, said valve also including upper and lower valve seats. and a vertically movable valve member between them normally engaging the lower seat and adapted to be pushed by said skirt up from the lower seat to the upper seat, a pair of laterally spaced arms pivotally mounted at the top of the guard at opposite sides of said valve and normally extending forward and backward from their pivots, a handle connected with the front ends of the armsand adapted to be swung upward to swing their rear ends down to permit the. neck of an oxygen generating canister in the guard to be moved up behind them, and means at said rear ends of thearms for engaging the bottom of the enlargement at the upper end of the canister neck to push it upward to actuate the valve when said handle is swung downward again, whereby to lift the skirt to push said valve member up against said upper seat, said means being formed to engage the lower end of the valve skirt in the absence of a canister and to lift itonlyfarenough to unseat said valve member from the lower valve seat without causing it to engage the upper seat.

12. In oxygen breathing apparatus, a canister guard, a vertically movable oxygen generating canister removably disposed in said guard and having a neck with an enlarged upper end, a slide valvemounted-on top of the guard and provided at itsbottom. with a sliding skirt, said valve also including upper and lower valve seats and a vertically movable valve member between them normally engaging the lower seat and adapted to be pushed by said skirt up from the, lowertseat to the upper seat, a pair of laterally spaced arms pivotally mounted at the top of the guard at opposite sides of said valve and normally extending forward and -backward from their pivots, a handle connected with the front ends of the arms and adapted. to be swung upward, to swing their rear ends down to permit the neck of an oxygen generating canister in the guard to be moved up'behind them, means at said rear ends of the arms; for engaging the bottom of the enlargement at the upper end of the canister neck to push it upward to actuate the valve when said handle is swung downward again, whereby to lift the skirt to push said vvalve member up against said upper seat, said means being formed to engage the lower end of the valve skirt in the absence of a canister and to lift it only far enough to unseat said valve member from the lower valve seat without 8 causing it to engage "the upper seat, and" a member projecting fromthe lowered handle into the guard and adapted to engage the bottom of said enlarged portion of the canister neck to support the canister in a stand-by position below saidarms.

13. In oxygen breathing apparatus, a guard, a vertically movable oxygen generating canister removably disposed in said guard and having a neck with an enlarged upper end, a slide. valve above the guard provided with an opening in its bottom, for reception of said enlarged upper end of'the canister neck and also provided with a vertically movable valve member above said opening; and apparatus for moving the canister upward and holding it -'in it-s upper position comprising supporting means adjacent the bottom of the valve, a pair of laterally spaced arms pivotally connected to said means on opposite sides of the valve near .itsfront and normally-extending forward and backward therefrom, a handle connected with the front ends of the arms and adapted to be swung upward to swing their rear ends down to permit the neck of the canister to be moved up behind them, and means on said rear ends of the arms for engaging the bottom of theenlarged upper end of thecanister neck to push it upward to raise the valve member when said handle, is. swung downward again, a bracket fastened to the back of the handle and provided with vertically spaced flanges having axially aligned openings, therethrough and notches in their opposite side edges, a latch slidably disposed in said openings and projecting above the upper flange, an inverted U-shape slide member slidably mounted in said notches,

a pin extending: transversely through said' latch and the opposite sides of said slide member directly below said upper flange, a-coil spring on the latch compressed beturn said pin and the lower flange of the bracket, and a pin projecting forward from said guard above the latch and having -a headengaging the, front surface of the upper end of the latch.

References Cited in the .fil'e of this patent UNITED STATES PATENTS Number Name Date 928,978 Jaub'ert July 27, 1909 1,772,674 Markus Aug. 12, 1930 FOREIGN PATENTS Number Country Date 6,966 Great Britain of 1910 

